Course material endpoints

Method	Endpoint	Description
POST	/v1/course-materials	Create a course material
GET	/v1/course-materials/:id	Fetch a single course material
PATCH	/v1/course-materials/:id	Partially updates a course material
DELETE	/v1/course-materials/:id	Permanently delete a course material
GET	/v1/course-materials	Fetch a list of course materials